Question

the given data represents a frequency distribution of the f - scale intensities of recent tornadoes. use the frequency distribution to construct a frequency polygon. does the graph suggest that the distribution is skewed? if so, how?
construct a frequency polygon using the data. choose the correct graph below.
does the graph suggest that the distribution is skewed? if so, how?
a. the distribution appears to be skewed to the left (or negatively skewed).
b. the distribution does not appear to be skewed.
c. the distribution appears to be skewed to the right (or positively skewed).
d. the distribution appears to be skewed to both sides.
tornado f - scale frequency
0 25
1 19
2 1
3 2
4 1

Explanation:

Step1: Recall frequency polygon concept

A frequency polygon is constructed by plotting the mid - points of each class interval on the x - axis and the corresponding frequencies on the y - axis, then connecting the points with line segments.

Step2: Analyze the given data

The tornado F - scale values are 0, 1, 2, 3, 4 with frequencies 25, 19, 1, 2, 1 respectively. The higher frequencies are for lower F - scale values (0 and 1).

Step3: Determine the shape of the distribution

When the higher frequencies are on the left - hand side of the graph and the tail extends to the right, the distribution is skewed to the right (positively skewed). When the higher frequencies are on the right - hand side and the tail extends to the left, the distribution is skewed to the left (negatively skewed). Here, since higher frequencies are for lower F - scale values (left side of the x - axis), the tail extends to the right.

Answer:

A. The distribution appears to be skewed to the right (or positively skewed).